Confronting uncertainty in wildlife management: performance of grizzly bear management
Download the paper at http://dx.plos.org/10.1371/journal.pone.0078041
Scientists from the Raincoast Conservation Foundation, Simon Fraser University, and University of Victoria have authored the first peer-reviewed study of British Columbia’s controversial grizzly bear management. Conclusions from “Confronting uncertainty in wildlife management: performance of grizzly bear management” published online in the international journal PLOS ONE, cast doubt on the BC government’s claim that “sound science” is used to manage the trophy hunt.
The scientists used government data on all human-caused mortality from 2001-2011 to determine if BC’s grizzly management met its own objectives (maintaining all human-caused kills below pre-determined limits). In this period, out of an estimated population of 15,000 bears, over 3500 bears (including over 1200 females) were killed, including over 2800 bears (over 900 females) by legally-sanctioned trophy hunting. The scientists found that total kills commonly exceeded limits set by management policy. These “overkills” occurred at least once in half the populations open to hunting. Disturbingly, these overkills were particularly common for females, the reproductive powerhouses of the species.
Kyle Artelle, Raincoast biologist, SFU PhD student, and lead author says “These overkills are a serious concern because the biology of grizzly bears makes them highly vulnerable to excessive mortality. They have great difficulty recovering from population declines.” BC also represents one of the last strongholds for North American grizzly bears, which have lost about half their continental range since European colonization. Even in BC about 1/3 of populations have either gone extinct, are currently threatened, or are closed to hunting, often for conservation concerns.
The team of wildlife and fisheries scientists also assessed how uncertainty in management might affect the likelihood of accurately detecting overkills. What they found was concerning: given unknowns in management (such as the actual number of bears in the hunted populations in BC) they found that mortality limits calculated by the government might have been too high. As a result, overkills might have occurred in 7 out of every 10 cases (populations over three study periods), , or up to 5 times more often than previously assumed.
This comes as no surprise to Jessie Housty, tribal councillor of the Heiltsuk First Nation. She questions the BC government claim that sound science is used to manage the hunting of grizzlies on the Central BC Coast, an area where the provincially sanctioned trophy hunt is at odds with tribal law, which prohibits it. She emphasizes that government biologists conduct no on-the-ground inventory of bears in that area. “How could the government possibly have a solid understanding of these bears they condemn to the hunt without setting foot in our Territory?”
Dr. Paul Paquet, Senior scientist at Raincoast and co-author, notes additionally “We analyzed only some of the uncertainty associated with grizzly management and found it might be contributing to widespread overkills. I’m not sure how the government defines “sound science”, but an approach that carelessly leads to widespread overkills is less than scientifically credible”.
Dr. Chris Darimont, professor at University of Victoria and Raincoast science director expresses concern this way, “Ignoring uncertainty – in dimensions such as true population size – is like playing Russian Roulette. As the history of wildlife management has shown repeatedly, the consequences of not accounting for the unknowns are grave”.
Fortunately, despite these problems, management does have an easy option for avoiding overkills through changes to hunting permit allocation. Artelle says “Reducing the hunt could have prevented most overkills, even considering uncertainty and other sources of mortality, such as car accidents, animal control kills, and poaching.”
This is not the first time Raincoast has raised concerns about BC’s grizzly trophy hunt. Because of a Raincoast submission outlining sustainability concerns, the European Union has banned the import of BC grizzly parts since 2002. Raincoast has also taken a direct approach to protecting bears by purchasing Guide Outfitting licenses, which eliminated the commercial hunt from almost 30,000 km2 of the BC coast.
Importantly, science is only one aspect of wildlife management. This hunt in particular is highly contentious and is strongly opposed by First Nations, environmentalists, and, according to the most recent McAllister Research Poll, by 80% of British Columbians. Although the team of biologist’s study reveals that this hunt is not managed by “sound science”, addressing scientific shortfalls would not address the broader societal concerns. As Chris Genovali, Executive Director at Raincoast says, “Given widespread public disapproval for this ethically and culturally unacceptable trophy hunt, current Provincial management of grizzlies seems to be driven more by bad political science than good biological science.”
Despite multiple attempts data were not originally shared by the Province until Raincoast and Ecojustice won a Freedom of Information request in the Supreme Court of BC. For this work, however, managers were helpful in providing data and even confirming the preliminary results of our audit.
Please see attached map of overkills across BC and figure showing wide uncertainty in population estimates reported by the Provincial government. Both are copyright to authors but can be used freely by permission in any media.
Additional stunning high resolution photographs of bears with full permission granted are available on request.
The open access article will be available online at http://dx.plos.org/10.1371/journal.pone.0078041 at 5 PM Eastern on November 6, 2013.
For more information please contact
Lead author, Biologist with Raincoast Conservation Foundation and PhD student at Simon Fraser University, Earth 2 Oceans group
Dr. Chris Darimont
Biologist with Raincoast, and Assistant Professor at University of Victoria, Geography Department